Electrical induction coil and method of manufacture thereof



G. E. HORN 1,815,620

ELECTRICAL INDUCTION COIL AND METHOD OF MANUFACTURE THEREOF July 21,1931.

Filed Oct. 31, 1928 2 Sheets-Sheet l K HNVENTOR BY a ATTORNEY July 21,1931. G HORN 1,815,629

ELECTRICAL INDUCTIQN COIL AND METHOD OF MANUFACTURE THEREOF Filed Oct.31, 1928 2 Sheets-Sheet 2 BY 1 %WW4L ATTORNEY.

, Patented July 21,1931.

PATENT OFFICE UNITED STATES- GEORGE E. HORN, OF FORT WAYNE, INDIANA,ASSIGNOR- TO GENERAL CABLE COR-- PORATION, OF NEW YORK, N. Y., ACORPORATION OF NEW JERSEY ELEOTBICAEINDUCTION COIL AND METHOD OFMANUFACTURE THEREOF Application filed October 31, 1928.

This invention relates to improvements in electrical induct-ion coilsand methods of manufacture thereof, more particularly to a unit coilhaving a primary and a secondary winding of very fine wire; such ascoils usufrom which to conveniently make an induction coil, which packconsists of a winding formed of a multiplicity of layers, usually of asingle length of wire. arranged in close spiral formation disposed insuccessive order, one layer superimposed upon another,

which winding preferably includes portions of the wire permanentlyplaced toform, correspondingly, primary and secondary circuits, andinitial and medial coiled portions transiently placed, whereby terminalconnections may be expeditiously attached re spect-ively to the ends ofthose portions for said circuits. Further objects of the invention areto provide an expedient to assist artisans in selecting the ends of thewires of which primary and secondary circuits are formed in a coil pack,to thereby facilitate the application of terminal connections thereto;and to reduce the number of and simplify the mechanical and manualoperations hitherto required in the manufacture of completed coils ofthe class described.

It has been found of advantage in the winding of coil units havingprimary and secondary circuits, to perform the entire winding with asingle Wire in a continuous operation, and attach the terminalconnections for the two circuits subsequently, because of accelerationof the winding operation. However, when the wires forming the coils areexceedingly fine, considerable difliculty has been experienced, inlocating and drawing out the ends of the wires of which the circuits areformed to permit of the at tachment thereto of the terminal connectionswithout disturbance of the permanent turns of the wire in said circuits.The present invention enables such advantage to be secured without thedifficulty above referred to.

Serial No. 316,328.

struction illustrated in the accompanying drawings, in which:

I Fig. 1 is a perspective view of the unit coil completed and with itsterminal connections attached; v

Fig. 2 is 'a perspective view of an unfinished coil pack showing themedial porgion of the wire partially withdrawn thererom;

Fig. 3 is a diagram of one end of the unfinished pack; and

Fig. 4 is a diagrammatical elevation projected from Fig. 3, a portionbeing broken away.

The illustrations of the invention, Figs. 3 and 4 are drawn uponadisproportionate scale, the wire 5 forming the winding for the coil 6,appearing as magnified, and the number of layers 7 and 8 thereof beingnumerically less as compared with an actual structure embodying theinvention, the diagrammatical form of illustration being resorted to forthe sake of convenience in showing the relative positions of the severalportions of the winding of the wire.

The pack 6 is initially formed by winding about a tubular core 9, a wire5 of insulated wire in spiral formation in successive layers, one uponanother, the layers 7 being first wound upon the core, there beingintroduced retaining members 10 during the winding operation wherebyeach layer is surrounded by a corresponding retaining member whencompleted. Said retaining membprs consist of strips of pliant insulatingmaterial, such as paper, each strip being of a size sufficient to extendcompletely around the layer, with its ends overlapping. The layers 7 aresulficiently numerous to form a primary circuit of such electricalcharacteristics as may be predetermined.

Upon the completion of the group of layers 7 there is wrapped thereon anindicating member 11 consisting of a paper strip of sufficient length topass around the group several times, which strip is of a colorcontrasting sharply from that of the retaining members 10. As the member11 is wrapped in place, the wire 5 is wound upon the indicat- 60 Theseobjects are accomplished by the coning member spirally outward from theadjacent layer 7 so that a series of additional turns 12 of said wireare established in a plane beyond that of the adjacent ends'of thelayers 7 and between the layers of the indicating member, the margin ofwhich indicating member and those of the retaining members 10 extendoutwardly beyond the ends of the permanent layers 7 and 8 of the wire.Upon the indicating member 11 is wrapped a second indicating member 13,also consisting of a paper strip of sufficient length to form severallayers, the strip 13 being of a color distinctive from those of theretaining members and the other indicating member, and as the member 13is wrapped in place, the wire 5 is wound thereon spirally inward so thata second series of addltional turns 14 are established between thelayers of said second indicating member 13. The layers 8 are then woundin place, with a retaining member 10 interposed between each layer, andupon completion of the outermost of the layers 8 a covering 15 isapplied to the pack to prevent disarrangement of the layers.

The completed winding of the wire in the pack is constituted of aninitial removable portion consisting of a number of turns 16 that arewound so as to lay out beyond the general plane of the adjacent ends ofthe layers 7 and 8; and the innermost of the layers 7 is composed ofpermanently placed turns that are a continuation of the initial turns16. The last turn 17 of the second of the la ers 7 which next overliesthe innermost 0 said layers, is spaced inwardly from the general planeof the adjacent ends of the layers 7 and 8 so that the turns 16 of theinitial portion of the winding, and those immediately adjacent theretoin the innermost layer 7, are relieved from pressure of the overlyingturns of the wire. The initial turns 16 are yieldingly held in positiontemporarily by the overlying retaining member 10, and may readily bedrawn outwardly from place and made accessible when required. Likewise,the last turn 18 of the second of the layers 8 that overlies theindicating member 13 is spaced inwardly from the general plane of theadjacent ends of the layers 7 and 8, so that the turns 12 and 14 of themedial portion of the winding are relieved from excessive pressure fromthe overlyin layers. Thus, the turns 12 and 14 are yiel ingly held inposition temporarily between the layers of the indicating members andmay readily be drawn outwardly from place and made accessible whenrequired.

The winding throughout its various portions, as shown and describedherein, is of a single continuous wire, the initial and medial portionsbeing readily accessible and withdrawable, while the layers 7 and 8, forthe primary and secondary circuits, are firmly'and ermanently retainedin place within the pack.

The pack thus prepared is then transformed and a unit induction coilmade therefrom, by unwinding from the pack the initial turns 16 to formone of the terminals 20 of the primary coil formed by the layers 7; themedial portion of the winding is unraveled from the pack and severed toform, respectively, the other terminal 21 for said primary coil, and oneof the terminals 22 for the secondary coil that is composed of thelayers 8; and the-extreme end portion of the outermost layer 8 isunwound sufiiciently to form the other terminal 23 for said secondarycoil.

Each of said terminals 20, 21, 22 and 23, have attached thereto in theusual manner a corresponding terminal connection 20, 21', 22 and 23,which terminals with their attached connections are fixed u on the packin spaced relation with each other by means of suitable adhesive anchorstrips 24 and 25 as in the customary manner.

As the method by which the entire winding for the unit induction coil isperformed with a single wire, the operation is more or less continuousand expeditious; and by incorporating in the pack the initial and medialremovable surplus turns of the wire offset from permanent turns to formcorres onding terminals for the primary and secon ary circuits,disarrangement of the permanent turns of the layers is obviated,inasmuch as the removable portions of the winding are retainedtemporarily in definite locations until their unraveling from the packis required.

A feature of the invention consists in the inclusion in the pack of theindicating members 11 and 13 upon which the medial turns of the wire arewound. The two indicating members, difi'ering in color from each otherand from the adjacent retaining members, enables the artisan whenapplying the terminal connections, to locate in the pack the medialremovable turns without search.

Also, the retention within the pack of the initial and medial turns ofthe winding until required for the attachment of the terminalconnections is of advantage, especially when the winding is of very finewire, as disarrangement, entanglement, confusion and loss of theterminal ends of the coils are circumvented.

The invention may be applied with facility in the manufacture of unitswherein the coils are composed of coarse wires, and the indicatingmean-s may be constituted of a single strip, or of several strips spacedapart with insulating material (not shown) disposed therebetween shouldheavy insulation between the coils be desired. The function of theindicating member primarily is to temporarily sustain the medial portionof the wire in an accessible and easily located position in theembryonic member to guide the artisan when drawing said portion out fromterminals for the coils without breaking thethe pack that it may besevered to provide terminals away from the permanent turns or otherwisedisturbing the layers thereof.

Numerous other modifications in the construction and arrangement of theindicating member and other parts may be resorted to by the exercise ofskill without departure from the spirit of the invention.

What I claim is 1. A pack from which to make an induction coil unit,containing a winding formed of a wire arranged in a multiplicity ofpermanent layers disposed in successive order,

one surrounding another, a number of remov able initial turns of thewire at the commencement of the first of said layers, a removable medialportion consisting of a number of additional turns of the wire, saidinitial and additional turns being accessibly disposed respectively inthe pack out beyond the adjacent ends of the corresponding permanentlayers to permit withdrawal thereof to provide corresponding terminalsfor the coils of said unit, and means included in said pack forsupporting said initial turns in accessible position beyond the adjacentends of the permanent layers.

2. A pack from which to make an induction coil unit, consisting of awire wound in a series of layers, one surrounding another; indicatingstrips interposed between two adjacent intermediate layers of saidseries; and supporting strips interposed respectively between the otherlayers, said indicating strips being distinguishable from saidsupporting strips, a medial portion of said wire being entwined .withsaid indicating strips and accessibly supported therein beyond the endsof said layers to permit the withdrawal of several turns of wire, toprovide corresponding terminals for the coils of said unit.

3. A pack from which to make an induction coil unit, consisting of awire wound in a series of layers, one surrounding another; indicatingstrips interposed between two adjacent intermediate layers of saidseries; and an additional portion of said wire connecting. saidintermediate layers supported by said indicating strips and accessiblydisposed at one end of the pack beyond said layers to permit withdrawalof said portion to provide corresponding terminals for the coils of saidunit.

4. A pack from which to make an induction coil unit, consisting of awire wound in two series of layers connected b an additional portion ofsaid wire that as numerous turns arranged in the pack beyond saidlayers; a supporting strip interposed between each layer and the layeradjacent thereto in each series; and an indicating means distinguishablefrom said supporting strips, disposed between said two series, saidadditional portion of the wire being related to said indicatng means soas to be supported and readily located and unraveled when required toprovide corresponding terminals for the coils of said unit.

5. A pack from which to make an induction coil unit, consisting of apack in which two permanent coils formed of a continuous wire arecontained, there being an additional portion of said wire initiallyconnecting said coils removably disposed in said pack beyond theadjacent ends of said coils, to be subsequen'ly located, drawn out andsevered to provide a corresponding terminal for each of said coils.

6. A pack from which to make an induction coil unit in which member twocoils formed of a continuous wire are permanently disposed, and in whichone of the ends of said wire and a medial portion thereof between saidcoils are disposed in said member aside from said permanently disposedcoils so as to be readily located, drawn out and severed to providecorresponding terminals for said coils.

7. A pack from which to make an induction coil unit, consisting of awinding formed of a continuous wire, two portions of which are eacharranged in a multiplicity of permanent layers, one surrounding another,and supporting strips interposed between said layers respectively, thesides thereof extending beyond the ends of said layers, an initialportion of said Winding contiguous with the first layer thereof beingyieldingly held in said pack by the extendmg part of the overlying stripbeyond the ad acent ends of said layer, and a medial wound portion ofsaid wire connecting the two first portions, and held yieldingly in saidpack beyond the ends of the corresponding layers, said initial andmedial ortions being accessibly disposed to permit ing drawn out andsevered to provide corresponding terminals for said induction coil unit.

8. A pack from which to make an induction coil unit, consisting of awinding formed of a continuous wire, two portions thereof having each aseries of permanent layers constituting a primary and a secondary coil,supporting strips interposed between said layers respectively, and twoindicating strips of contrasting colors interposed between said coils, amedial portion of said winding connecting said coils removably supportedby and accessibly disposed in said indicating strips beyond the ends ofsaid coils whereby said medial portion may be readily located and drawnout to provide a corresponding terminal for each coil.

9. A pack from which to make an induction coil unit, consisting of aWinding to provide primary and secondary coils and a medial portionconnecting said coils, and an indicating means interposed between saidcoils and extending outwardly therefrom, by which means said medialortion is removably supported and accessi ly disposed beyond thecorresponding ends of said coils, whereby said medial portion may bereadily located and drawn out from the pack to provide a correspondingterminal for each coil.

10. The method of making an induction coil unit, consisting in preparinga pack by winding a continuous wire u on a core to form the primary andsecon ary coils for said unit and with a removable medial rtion of thewire connecting said coils, an in terposing between the layers of eachcoil corresponding supporting strips, and between said coils indicatingstrips, distinguishable from said su rting strips, in such manner as toremova y sup ort said medial portion in the pack beyond t e adjacentends of said coils in an accessible position; subsequently drawing outsaid medial ortion and ends of said wire from said mem er; and severingsaid medial portion, to provide terminals for said primary and secondarycoils.

11. A pack from which to make an induction coil unit, consisting of awire wound to 1provide primary.and secondary coils, each aving numerouslayers; retaining strips between said layers extending beyond the endsthereof, and a medial wound portion connectingsaid coils removablydisposed in the pack beyond the ends of the ad acent layers, the layernext succeeding the layer connected wlth said removable portionterminating at a point spaced inwardly from the ends of the overlyinglayers.

12. As a new article of manufacture, a multi-layer coil windin formedfrom a continuous wire, and in WlllCh the layers are substantiallyco-extensive and are separated from each other b strips of insulatingmaterial which exten beyond the edges of the coil winding, characterizedby the fact that at least one of the coil layers is wider than andextends beyond the other layers, whereby without disturbing adjacentcoil layers several turns of wire may readily be withdrawn from theedge-of the wider coil layer to provide a terminal for the coil winding.

13. A pack from which to make an induction coil unit, consisting of awire wound to provide primary and secondary coils each composed ofnumerous permanently disposed layers of the wire, and having portionsremovably disposed in the pack located therein axially beyond the endsof the adjacent layers, the layer in each coil next succeeding thecorresponding removable portion being offset inwardly from the overlyinlayers.

14. A pack from which to ma e a coil unit, consisting of a wire wound toprovide a coil having a series of layers each composed of permanentlyplaced turns; retaining strips between said la ers; and a removablewound portion of sai wire disposed in the pack connecting the ends oftwo adjacent layers,

the layer next succeeding the connected layers being ofi'set inwardlybeneath the correspondin ends of the overlying layers of the coil to tereby relieve said removable portion from pressure of the overlyingturns and to permit withdrawal of said portion from the pack.

15. An electrical coil structure havin numerous wound layers of wire theen s of which layers terminate substantially in a common plane extendingat ri ht angles to the axis thereof, and two ad jacent interposed layersconnected at one end with each other that are characterized byterminating with respect to their connected ends at a point spacedaxially from the plane of the coriesponding ends of the former layers.

16. An electrical coil structure formed from a continuous wire in whichare included primary and secondary coils each having numerous overlyinglayers and an' additlonal coil extending out beyond the ends of adjacentlayers of said primary and secondary coils and connecting said prima andsecondary coils; supporting strips disposed between the layers of saidprimer and secondary coils; and additional strlps, distinguishable fromthe first named strips, supporting said additional coil in a locationadj acient the connected ends of the first named cm s.

17 The method of making an electrical coil structure which compriseswinding a coil in successive layers, interposing supporting stripsbetween the layers, interposing distinctive indicating means betweenmedial layers of said coil, extendin one of the medial layers adjacentsaid in icating means out beyond the ends of adjacent layers, andsubsequently drawin out the extended ortion of the said medial layer torovi e a terminal intermediate the ends 0 the coil windin 18. T e methodof making an electrical coil structure which comprises winding a coil insuccessive layers, interposing supporting strips between the layers,interposing distinctive indicating means between medial layers of saidcoil, extending one of the medial layers adjacent said Indicating meansbut beyond the ends of adjacent layers, supporting the extended portionof the said medial layer by said indicating means, subsequently drawinout the extended portion of the said medial ayer, and severing theextended portion to provide coil terminals intermediate the ends of thecoil windin 19. The method of making an electrical coil structure whichcom rises winding a continuous wire in a plurality of overlying la ersto provide primary and secondary coi s, inserting supporting stripslonger than the coil layers between said layers during the windingoperation, and, during the winding operation, winding a plurality ofturns of wire connecting said primary and secondary coils in thesupporting strips out beyond the ends of adjacent coil layers, wherebythe said turns subsequently may be readily withdrawn from the end of thecoil structure to provide coil terminals.

In testimony whereof I afiix my signature.

GEORGE B. HORN.

